Abstract
1. The discharges of single X and Y ganglion cells (distinguished by a test of linearity of spatial summation) were recorded in the optic tract of anaesthetized, paralysed cats.
2. Fourier techniques were used to analyse the distribution of amplitudes of several component temporal frequencies in the maintained discharge. X and Y cells were distinguished by their mean rates, but not by the amplitude or variability of other component frequencies.
3. Sensitivities to moving sinusoidal gratings were measured by an automatic procedure in which stimulus contrast was adjusted to give the smallest modulation of discharge that reliably exceeded that of the relevant component frequency in the maintained discharge.
4. Spatial contrast sensitivity curves of X cells and of on-centre Y cells could be described by a model of the receptive field as two concentric Gaussian sensitivity profiles representing the centre and the antagonistic surround.
5. Changes in temporal frequency altered the shapes of the spatial contrast sensitivity curves of most units. For X cells sensitivity at the optimum spatial frequency was greater at a temporal frequency of 10·4 Hz than at lower or higher temporal frequencies. The relative sensitivity to low spatial frequencies improved as temporal frequency was raised from 0·16 to 20·8 Hz. The shapes of the contrast sensitivity functions of Y cells were less affected by changes in temporal frequency: at all spatial frequencies sensitivity was greater at 2·6 Hz than at lower or higher frequencies.
6. The effect of temporal frequency upon the shape of the spatial contrast sensitivity curve could be explained by assuming that the centre and surround changed their sensitivities without changing their characteristic radii. A simple model, using a temporal R—C filter in the surround pathway, predicted qualitatively similar changes in the shape of contrast sensitivity curves but failed to provide acceptable fits to the observations. A second model, which assumed that surround signals are delayed by a fixed amount before being combined with those from the centre, fitted the observations of most, but not all, X cells.
7. Dark adaptation produced changes in the shape of the spatial contrast sensitivity curve consistent with a reduction in the relative sensitivity of the surround, but did not bring about systematic changes in the space constants of the best-fitting theoretical curves.
8. The effects of adaptation level upon contrast sensitivity were expressed as plots of increment—threshold against mean illumination. The shallowest of these curves, obtained for the optimum spatial stimulus moving at about 10 Hz, had slopes averaging 0·77. Decreases in spatial or temporal frequency increased the slopes of the curves.
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Selected References
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- BARLOW H. B., FITZHUGH R., KUFFLER S. W. Change of organization in the receptive fields of the cat's retina during dark adaptation. J Physiol. 1957 Aug 6;137(3):338–354. doi: 10.1113/jphysiol.1957.sp005817. [DOI] [PMC free article] [PubMed] [Google Scholar]
- BARLOW H. B. Temporal and spatial summation in human vision at different background intensities. J Physiol. 1958 Apr 30;141(2):337–350. doi: 10.1113/jphysiol.1958.sp005978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Barlow H. B., Levick W. R. Three factors limiting the reliable detection of light by retinal ganglion cells of the cat. J Physiol. 1969 Jan;200(1):1–24. doi: 10.1113/jphysiol.1969.sp008679. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Barlow H. B., Levick W. R. Threshold setting by the surround of cat retinal ganglion cells. J Physiol. 1976 Aug;259(3):737–757. doi: 10.1113/jphysiol.1976.sp011492. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Baylor D. A., Hodgkin A. L. Changes in time scale and sensitivity in turtle photoreceptors. J Physiol. 1974 Nov;242(3):729–758. doi: 10.1113/jphysiol.1974.sp010732. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Blake R., Camisa J. M. Temporal aspects of spatial vision in the cat. Exp Brain Res. 1977 Jun 27;28(3-4):325–333. doi: 10.1007/BF00235714. [DOI] [PubMed] [Google Scholar]
- Cleland B. G., Enroth-cugell C. Quantitative aspects of sensitivity and summation in the cat retina. J Physiol. 1968 Sep;198(1):17–38. doi: 10.1113/jphysiol.1968.sp008591. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Daitch J. M., Green D. G. Contrast sensitivity of the human peripheral retina. Vision Res. 1969 Aug;9(8):947–952. doi: 10.1016/0042-6989(69)90100-x. [DOI] [PubMed] [Google Scholar]
- Enroth-Cugell C., Hertz B. G., Lennie P. Convergence of rod and cone signals in the cat's retina. J Physiol. 1977 Jul;269(2):297–318. doi: 10.1113/jphysiol.1977.sp011903. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Enroth-Cugell C., Hertz G., Lennie P. Cone signals in the cat's retina. J Physiol. 1977 Jul;269(2):273–296. doi: 10.1113/jphysiol.1977.sp011902. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Enroth-Cugell C., Lennie P. The control of retinal ganglion cell discharge by receptive field surrounds. J Physiol. 1975 Jun;247(3):551–578. doi: 10.1113/jphysiol.1975.sp010947. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Enroth-Cugell C., Robson J. G. The contrast sensitivity of retinal ganglion cells of the cat. J Physiol. 1966 Dec;187(3):517–552. doi: 10.1113/jphysiol.1966.sp008107. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Enroth-Cugell C., Shapley R. M. Flux, not retinal illumination, is what cat retinal ganglion cells really care about. J Physiol. 1973 Sep;233(2):311–326. doi: 10.1113/jphysiol.1973.sp010309. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hochstein S., Shapley R. M. Linear and nonlinear spatial subunits in Y cat retinal ganglion cells. J Physiol. 1976 Nov;262(2):265–284. doi: 10.1113/jphysiol.1976.sp011595. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hochstein S., Shapley R. M. Quantitative analysis of retinal ganglion cell classifications. J Physiol. 1976 Nov;262(2):237–264. doi: 10.1113/jphysiol.1976.sp011594. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kaplan E., Marcus S., So Y. T. Effects of dark adaptation on spatial and temporal properties of receptive fields in cat lateral geniculate nucleus. J Physiol. 1979 Sep;294:561–580. doi: 10.1113/jphysiol.1979.sp012946. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kelly D. H. Adaptation effects on spatio-temporal sine-wave thresholds. Vision Res. 1972 Jan;12(1):89–101. doi: 10.1016/0042-6989(72)90139-3. [DOI] [PubMed] [Google Scholar]
- Lennie P. Perceptual signs of parallel pathways. Philos Trans R Soc Lond B Biol Sci. 1980 Jul 8;290(1038):23–37. doi: 10.1098/rstb.1980.0080. [DOI] [PubMed] [Google Scholar]
- Lennie P. Scotopic increment thresholds in retinal ganglion cells. Vision Res. 1979;19(4):425–430. doi: 10.1016/0042-6989(79)90108-1. [DOI] [PubMed] [Google Scholar]
- Movshon J. A., Thompson I. D., Tolhurst D. J. Spatial and temporal contrast sensitivity of neurones in areas 17 and 18 of the cat's visual cortex. J Physiol. 1978 Oct;283:101–120. doi: 10.1113/jphysiol.1978.sp012490. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pasternak T., Merigan W. H. The luminance dependence of spatial vision in the cat. Vision Res. 1981;21(9):1333–1339. doi: 10.1016/0042-6989(81)90240-6. [DOI] [PubMed] [Google Scholar]
- Rodieck R. W. Quantitative analysis of cat retinal ganglion cell response to visual stimuli. Vision Res. 1965 Dec;5(11):583–601. doi: 10.1016/0042-6989(65)90033-7. [DOI] [PubMed] [Google Scholar]
- Rodieck R. W., Stone J. Analysis of receptive fields of cat retinal ganglion cells. J Neurophysiol. 1965 Sep;28(5):832–849. doi: 10.1152/jn.1965.28.5.833. [DOI] [PubMed] [Google Scholar]
- SCHADE O. H., Sr Optical and photoelectric analog of the eye. J Opt Soc Am. 1956 Sep;46(9):721–739. doi: 10.1364/josa.46.000721. [DOI] [PubMed] [Google Scholar]
- Virsu V., Lee B. B., Creutzfeldt O. D. Dark adaptation and receptive field organisation of cells in the cat lateral geniculate nucleus. Exp Brain Res. 1977 Jan 18;27(1):35–50. doi: 10.1007/BF00234823. [DOI] [PubMed] [Google Scholar]
